Safe hair care spares hair, Johns Hopkins dermatologists report

A common cause of hair loss and breakage known as acquired trichorrhexis nodosa, or TN –often more prevalent in African-Americans — can actually be remedied through appropriate use of cleansing products, hair care and styling practices, say researchers at Johns Hopkins.

"It's imperative that we offer dermatologist and patients alike easy tips for resolving TN, one of the few forms of hair loss that can be resolved fairly quickly with nonmedical options," says Crystal Aguh, M.D., assistant professor of dermatology at the Johns Hopkins University School of Medicine and co-author of Fundamentals of Ethnic Hair: The Dermatologist's Perspective. "Our recommendations are acceptable for those of all ethnic backgrounds experiencing hair breakage, and dermatologists should feel comfortable discussing these techniques with every patient seen."

In a literature review published ahead of print in the Journal of Dermatological Treatment, the investigators outline risk factors and simple recommendations for dermatologists, who are often uncomfortable with advising patients, especially those of color, on appropriate practices necessary for avoiding hair loss and breakage.

In the report, researchers analyzed the risk factors for TN. They found that thermal styling tools, such as the use of flat irons and blow dryers, as well as chemical processing, such as permanent dye and straightening, tend to damage the protective outer layer of the hair shaft, called the cuticle. This can alter the hair's protein structure, which causes the cortical fibers to be exposed and fray, leading to weak points where breakage occurs.

Patients of African heritage (African-American and Afro-Caribbean) who tend to have tightly coiled hair are at increased risk for hair loss and damage from TN. This is because there are structural differences within the hair shaft — African hair fibers have an asymmetric shape and curvature, resulting in points of geometric weakness in the hair shaft. Curly hair also has differences in hydration properties, causing it to be drier and more susceptible to breakage.

Cleansing is the cornerstone of any health hair regimen, says Aguh. Inadequate cleansing of the hair and scalp can result in the buildup of product residue, leading to problems such as seborrheic and irritant dermatitis.

As part of the literature review, investigators also describe simple over-the-counter, nonmedical remedies that can be recommended by dermatologists when treating patients with TN. First, choosing the appropriate shampoo based on hair types, the researchers say, is incredibly important when trying to reduce breakage and loss. Most shampoos include surfactants, which are the active ingredients that bind sebum and water. There are three types of surfactants to look for when selecting a shampoo — anionic, amphoteric and nonionic. Anionic surfactants tend to be best suited for those with oily hair and are very effective at cleansing the hair, but this can leave the hair feeling dry and prone to breakage. Nonionic or amphoteric surfactants are recommended for those with natural black hair or dry, damaged or color-treated hair. These types of shampoos are gentler and less likely to strip the hair of moisture.

Second, the frequency at which the hair is cleansed is key in minimizing the impact of TN. Frequency varies greatly based on many factors, such as age, ethnic origin and condition of the hair. Those with tightly curled hair types should shampoo their hair less frequently, since sebum has a harder time coating this particular type of hair strand. Patients with straight hair should shampoo more frequently because sebum coats the entire strand, leading to oily hair.

"Patients with dry, damaged or tightly curled hair should limit their shampooing to no more than once per week. Those with straight hair, however, can shampoo daily," recommends Aguh.

Third, conditioning the hair is arguably one of the most important steps for a healthy hair regimen, say the investigators. Conditioners increase hair manageability, help eliminate static electricity and can temporarily mend hair shaft damages. They come in many different formulations depending on the desired effect — rinse-out, deep, leave-in and protein-containing. Rinse-out conditioners are applied immediately after the use of shampoo and rinsed out with water. While rinse-out conditioners increase manageability and add shine, they're less effective in repairing hair damage due to their short contact time with the hair. Unlike rinse-out, deep conditioners are left on the hair for at least 10 minutes and include the use of heat. Since they are usually formulated as deep creams, they enhance moisture in the hair. Deep conditioners are beneficial for severely damaged hair. Leave-in conditioners are put in the hair after shampooing and conditioning, and are not rinsed out. Leave-ins can be applied daily and are ideal for preventing damage from everyday grooming. The most beneficial conditioning treatment for those with dry and damaged hair is protein-containing conditioners. These can be formulated as rinse-out, deep or leave-in. Though protein-containing treatments help with breakage, it is recommend to only apply on a monthly or bimonthly basis, since overuse can lead to brittleness.

Lastly, another way to help minimize hair breakage and prevent or treat TN is to try the repurposed soak-and-smear method for hair care. This method increases moisture retention, which in return enhances hair elasticity and reduces tangles. It forms increased protection from damage. The repurposed soak-and-smear method for hair care is as follows:

Shampoo and/or condition the hair normally and lightly blot hair with a towel.

Follow with the application of a water-based leave-in conditioner to the hair.

Immediately apply an oil or thick, occlusive moisturizer, such as coconut oil, olive oil, jojoba oil, petrolatum or mineral oil, to the hair.

Allow the hair to air dry and style as desired.

This method can be completed as often as needed throughout the week and modified depending on shampoo/conditioning needs. The repurposed soak and smear is especially beneficial for patients with tightly coiled hair, as it helps reduce dryness associated with overprocessing from heat and chemical applications.

These recommendations can greatly improve the hair condition of those with TN. Since hair is a nonliving tissue, total repair of the hair shaft is not possible. Implementation of proper cleansing and conditioning techniques, as well as proper product selection, improve the overall health of hair, making it more resilient to trauma. "Patients need to be advised on how to improve the quality of their cleansing and conditioning routines," says Aguh. "These are the foundation of a healthy hair routine."

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Additional authors of this study include Shawn G. Kwatra of the Johns Hopkins University School of Medicine and Alessandra Haskin of Howard University College of Medicine.